Adding rel="nofollow" to Comments in Drupal 6

By default in Drupal 6, only the Homepage link of a commenter has a rel="nofollow" attribute attached to it. The commenter has free reign on all the other anchor tags inside the body of the actual comment. In many cases this is unsuitable especially for SEO purposes.

Spammers like to leave links in comments to transfer Pagerank from your page to theirs. By adding a rel="nofollow" attribute, no Pagerank will be passed to the external page and it will also serve as a deterrent to adding external links in the first place.

At first you might think that you need to do some custom coding to achieve this functionality. In fact, it is there waiting to be enabled in Drupal 6!

Enable rel="nofollow" for Comment Bodies

The instructions below assume that you allow only the default Input Format of Filtered HTML for anonymous users. This tutorial can be easily adapted for other Input Formats.

1. Goto Administer >> Site Configuration (which is at /admin/settings)
2. Goto Input Formats (which is at /admin/settings/filters)
3. Look in the row for Filtered HTML and select configure.
4. Goto the tab at the top which says Configure.
5. Right at the bottom, check the checkbox which says Spam link deterrent.
6. Click Save configuration.

And voila, all links in comments will now have a rel="nofollow" attribute attached to them.

Now, even if a spam comment accidentally gets through to your website, at least no pagerank will be transferred to the spammy page. You would have also told search engines that you are not necessarily endorsing the external page in any way.

We hope this Drupal tutorial was useful.